New writer class for the skin detector

src/Root/SkinDetectorWriter.cpp

@@ -0,0 +1,43 @@
+#include "SkinDetectorWriter.h"
+#include "muCastorSkinHit.h"
+#include "TVector3.h"
+
+SkinDetectorWriter::SkinDetectorWriter(string filename) :
+    t_file(nullptr),
+    t_tree(nullptr),
+    t_buffer(nullptr)
+{
+    t_file = new TFile(filename.c_str(), "RECREATE");
+    t_tree = new TTree("muCastorMC", "muCastorMC");
+    t_buffer = new TClonesArray("muCastorSkinHit");
+
+    t_tree->Branch("CastorSkinHits", "TClonesArray", t_buffer, 32000, 99);
+}
+
+SkinDetectorWriter::~SkinDetectorWriter()
+{}
+
+void SkinDetectorWriter::add(int detID, float p_x, float p_y, float p_z,
+                             float m_x, float m_y, float m_z)
+{
+    TClonesArray& ref = *t_buffer;
+    int size = ref.GetEntriesFast();
+
+    muCastorSkinHit* new_hit = new(ref[size]) muCastorSkinHit();
+    new_hit->SetDetID(detID);
+    new_hit->SetPdgCode(13);
+    new_hit->SetMotherID(-1);
+    new_hit->SetPos (TVector3(p_x, p_y, p_z));
+    new_hit->SetMom (TVector3(m_x, m_y, m_z));
+}
+void SkinDetectorWriter::write()
+{
+    t_tree->Fill();
+    t_buffer->Delete();   // or t_buffer->Clear() ??
+}
+
+void SkinDetectorWriter::close()
+{
+    t_tree->Write();
+    t_file->Close();
+}